Compatibility Note: in LispWorks 4.4 and previous on Windows and Linux platforms,
:symbol-names-action t
would shorten symbol names to a three-character unique code. This has changed, as described above, in LispWorks 5.0.

Removing symbol names makes it very difficult to debug the application, and it is assumed that it is done after the application is essentially error free. However, some applications may make use of symbol names as strings, which may cause errors to appear only when the symbol names are removed. In some cases the easiest solution is to retain symbol names. This will result in a larger executable, though the size increase is usually small.

If you do want to remove symbol names and need to debug your application,
:symbol-names-action
takes these other values
:spell-error
,
:reverse
,
:invert
and
:plist
. In the case of
:spell-error
(which is probably the most useful), the last alphabetic characters in the first 6 characters of the symbol name are rotated by one, that is, A becomes B, g becomes h, and Z becomes A. This leaves the symbol names quite readable, but any function that relies on symbol names fails. A more drastic effect is achieved by the value
:reverse
, which reverses the symbol name. The value
:invert
just changes the case of every alphabetic character to the other case. This is more readable than
:spell-error
, but if the application relies on symbol names but does not care about case, the errors do not appear. The value
:plist
causes the symbol names to be set to the dummy name, but the old string is being put on the
plist
of the symbol
(get symbol `sys::real-symbol-name)
. The simple backtracer uses the property when it exists to get the symbol name.

After debugging your delivered application using
:spell-error
,
:reverse
,
:invert
or
:plist
, you may want the production build to be done with
:symbol-names-action t
to remove symbol names and achieve a small reduction in size.

Compatibility Note: in LispWorks 4.4 and previous on Windows and Linux platforms,
:symbol-names-action
allows the value
:dump
. This is no longer supported.